Stoker



Aug. 2, 1932. w. H. R. MARSDEN ET AL 1,870,015

STOKER Filed Oct. 13, 1927 2 Sheets-Sheet 1 Aug. 2, 1932. w. H. R. MARSDEN ET AL sToKER Filed Oct. 15, 1927 ZSheets-Sheet 2 y V W Patented Aug. 2, 1932 Uhll''ED4 STATES PA-rssr orties WLLIAM H. ROWLAM MARSDEN, F PITTSBURGH, PENNSYLVANIA, AND LONNIE EDWARD OSBORNE, DECEASED, LATE 0F ALLEGHENY COUNTY, PENNSYLVANIA, BY ZOLLIE Gr. OSBORNE, EXECUTRIX, OF BELLEVUE, PENNSYLVANIA, ASSIGNORS, BY .IVIESNE ASSIGNMENTS, TO THE 'STANDARD STOKER COTYIPANY, INC., OF NEW YORK, N. Y., A CORPORATION OF DELAWARE STOKER, ,v

Application filed October 13, 1927. Serial No. 225,906.

The invention relates to stokers for a plurality of furnaces, and more particularlyto stokers for firing the furnaces of marine boilers.

In marine service it is a common practice to use boilers of the Scotch type, a plurality of furnaces being built into and enclosed within the boiler, the several furnaces communicating with a common combustion chamber also enclosed within the boiler and which delivers the vapors of combustion through flue tubes to a breeching at the forward end of the boiler, which is in communication with the smoke stack.

In its broader aspects the invention is applicable to a battery or plurality of furnaces, however, they may be correlated and associated with one -or more boilers.

The objects of the invention are to provide asimple and highly efficient stoler and to provide means for the efficient delivery of fuel to the several furnaces.

A further object is to provide a pressure fluid supply system arranged for the easy L correction of any difficulties which may develop in connection with the delivery of the fuel.

The invention consists in a structure such as hereinafter described, and as illustrated in the accompanying drawings, in which:

Fig. 1 is a. longitudinal vertical central section through one of the furnaces of a Scotch boiler and the delivery end of a stolzer;

Fig. 2 is a front elevation of a portion of the boiler and its furnaces. with so much of a stoker and pressure fluid supply system shown applied thereto as appertains to the e invention, parts of the Stoker being broken awav;

Fig. 3 is an enlarged sectional view of the fuel distributor;

Fig. 4 is a section through a checlr valve incorporated in the pressure fluid supply system; and

Fig. 5 is a section through thehigh pressure control valve of the pressure iiuid supply system.

The invention is illustrated as applied to marine boilers of the Scotch type, though, broadly considered, the feature of importance is that by means of a unitary stoling device several furnaces may be simultaneously and properly fired.

At 22 is represented a boiler of the Scotch type, provided with a plurality of furnaces, as 24, 25 and 26, housed within it and opening through its back head. Each of the furnaces is provided with a bridge-wall, as 28, over which pass the vapors of combustion into a combustion chamber 29, also enclosed within the boiler, and which discharges through flue tubes into the breeching 31, which is in communication with the smoke stack, not shown.

Each of the furnaces is provided with a hand firing door, as 32, a grate 38, and an ash pit 34.A

Fuel is delivered by gravity through delivery chutes 43, 44, each leading to and discharging into a delivery tube, as 47, entering one of the furnaces through its back head, from which it is scattered over the grate area by a steam blast.

As shown most plainly in Fig. l the lower end of the conduit 44 terminates in an elbow 76, which delivers yinto the outer end of the distributor tube 47, setting through the back head of thefurnace 25. A steam nozzle 77 projects into the elbow through'its outer wall,

and delivers one or more steam jets through the tube 47 for forcibly throwing the coal into the fire boX. and scattering it over the grate 33. A deflector plate 78 projects forwardly from the upper side of the tube 47 for directing th-e fuel downwardly, the effective plane of this deiiector being so related to the bridgeewall 28 as to preventv any of the coal from going thereover into the chamber 29. An abutment 79 located slightly in advance of the bottom of the tube 47, and projecting slightly thereabove, arrests the lower stratum of the coal passing through the tube, and drops it upon the rear portion of the grate.

The lower end of the chute 44 is secured to a bracket attached to the outer face of the back head of the furnace by means of bolts, such as 81 (see Fig. The bracket 80 carries an upstanding apertured plate 82 known in practice as a draft ring. rlhe outer end of the distributor tube 47 fits within the aperture of this plate, and is attached to the lower end of the chute 44 by means of studs, as 83. These studs are threaded into lateral lugs on the tube 47 and project through lateral lugs on the chute, and the parts are secured together by suitable means.

Steam is delivered to the steam nipples 77, associated with the distributor tubes 47 of the several furnaces by a system of piping shown in detail in Fig. 2.

A low pressure pipe 97 leads from any suitable source of supply, such as a steam boiler, and branches to the nipples associated with the several furnaces, the main branches 98, 99 serving respectively the furnaces 24, 25 and 26. Their connections being the same, but one set will be described.

The line 98 is shown as leading directly to the nipple associated with the furnace 24, and a branch 100 therefrom, connected in by means of the T 101, leads to 'the nipple associated with the furnace 25. A shut-off valve 102 is placed in the pipe 98 beyond the T 101, and a similar valve 103 is placed in the branch pipe 100. Leads 104 and 105 conneet the pipes 98 and 101 with a steam gauge 10G for the purpose of indicating the pressure being supplied to the two nipples.

When the coal is wet, and especially when slack coal is used, there is apt to be a clogging at the base of the delivery chute, as 44, and in the distributor' tube 47, which the low pressure steam blast is not adequate to di. place. There is, therefore, provided a high pressure steam lead 107, which is connected in to the low pressure leads adjacent to each nipple. A branch of the high pressure lead 107 is shown at 108, and connected with pipe 98 at 109. A normally closed valve 110 is placed in each branch of the high pressure line, as at 111, and may be manually opened, as by means of a lever 119... A forwardly opening check valve 113 is placed in each of the low pressure lines, as at 114, for preventing the high pressure from backing up through the low pressure line when the valve 110 is open.

To facilitate inspection and the removal of any clogging material, a door 115 is placed in each of the chutes, as 44, immediately above its elbow.

lVhile there is shown and described a desirable form of construction, various changes in detail may be made within the scope of the invention.

We claim as our invention:

1. A stoker for furnaces comprising a gravity chute delivering to the furnace, the lower end of the chute being an approximately right-angled elbow, a steam nozzle located at the bow of the elbow and discharg-' ing .into the furnace, a system of valve controlled pipes for conveying steam at low pressure to the nozzle, and a system of valve controlled pipes for conveying` steam at high pressure to the nozzle through said low pressure line.

2. A stoker for furnaces comprising a gravity chute delivering to the furnace, the lower end of the chute being an approximately right-angled elbow, a steam nozzle located at the bow of the elbow and discharging nto the furnace, a steam pipe for low pressure leading to the nozzle and having a check valve therein for preventing back flow, and a valve controlled steam pipe for high pressure connected with the low presure pipe between the check valve and the nozzle.

lin combination, a furnace, a fuel distributor' tube delivering to the furnace, a steam pipe discharglnginto the tube, a low pressure steam lead to the pipe, a high pressure steam lead tothe pipe, a normally closed valve in the high pressure lead, and manual means for opening the valve.

ln testimony whereof we aiiix our signatures.

VM. HY. ROVLAND MARSDEN. ZOLLIE OSBORNE,

Eeeutrz'w of the Last l/V/ZZ cmd Testament of Lon/ne Edward Osborne, Deceased. 

